Teensy micro ros

#teensy   #microros  

---

Table of Content

Teensy micro ros

Add udev rule

copy udev file from https://www.pjrc.com/teensy/00-teensy.rules to /etc/udev/rules.d/00-teensy.rules

---

PlatformIO

Install PlatformIO

[env:teensy41]
platform = teensy
board = teensy41
framework = arduino
board_microros_distro = humble
board_microros_transport = serial
monitor_speed = 115200

lib_deps =
    https://github.com/micro-ROS/micro_ros_platformio

---

publisher example code

#include <Arduino.h>
#include <micro_ros_platformio.h>

#include <rcl/rcl.h>
#include <rclc/rclc.h>
#include <rclc/executor.h>

#include <std_msgs/msg/int32.h>

#if !defined(MICRO_ROS_TRANSPORT_ARDUINO_SERIAL)
#error This example is only avaliable for Arduino framework with serial transport.
#endif

rcl_publisher_t publisher;
std_msgs__msg__Int32 msg;

rclc_executor_t executor;
rclc_support_t support;
rcl_allocator_t allocator;
rcl_node_t node;
rcl_timer_t timer;

#define RCCHECK(fn) { rcl_ret_t temp_rc = fn; if((temp_rc != RCL_RET_OK)){error_loop();}}
#define RCSOFTCHECK(fn) { rcl_ret_t temp_rc = fn; if((temp_rc != RCL_RET_OK)){}}

// Error handle loop
void error_loop() {
  while(1) {
    delay(100);
  }
}

void timer_callback(rcl_timer_t * timer, int64_t last_call_time) {
  RCLC_UNUSED(last_call_time);
  if (timer != NULL) {
    RCSOFTCHECK(rcl_publish(&publisher, &msg, NULL));
    msg.data++;
  }
}

void setup() {
  // Configure serial transport
  Serial.begin(115200);
  set_microros_serial_transports(Serial);
  delay(2000);

  allocator = rcl_get_default_allocator();

  //create init_options
  RCCHECK(rclc_support_init(&support, 0, NULL, &allocator));

  // create node
  RCCHECK(rclc_node_init_default(&node, "micro_ros_platformio_node", "", &support));

  // create publisher
  RCCHECK(rclc_publisher_init_default(
    &publisher,
    &node,
    ROSIDL_GET_MSG_TYPE_SUPPORT(std_msgs, msg, Int32),
    "micro_ros_platformio_node_publisher"));

  // create timer,
  const unsigned int timer_timeout = 1000;
  RCCHECK(rclc_timer_init_default(
    &timer,
    &support,
    RCL_MS_TO_NS(timer_timeout),
    timer_callback));

  // create executor
  RCCHECK(rclc_executor_init(&executor, &support.context, 1, &allocator));
  RCCHECK(rclc_executor_add_timer(&executor, &timer));

  msg.data = 0;
}

void loop() {
  delay(100);
  RCSOFTCHECK(rclc_executor_spin_some(&executor, RCL_MS_TO_NS(100)));
}

Agent

Build

ros2 run micro_ros_setup create_agent_ws.sh

ros2 run micro_ros_setup build_agent.sh
source install/local_setup.bash

Run

ros2 run micro_ros_agent micro_ros_agent serial --dev /dev/ttyACM0

ROS

ros2 topic list
/clock
/micro_ros_platformio_node_publisher
/rosout

ros2 topic echo /micro_ros_platformio_node_publisher
#
data: 159
---
data: 160